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Oct 29, 2014
10/14

by
Wessels, Francois

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This article is from Cardiovascular Journal of Africa , volume 21 . Abstract Introduction: This project was based on the FIELD trial.1 It is a localisation of the study by Carrington and Stewart.2 The aim of the original study was to determine the impact of fenofibrate therapy on healthcare costs of middle-aged patients with type 2 diabetes at high risk of future cardiovascular events. Methods: The methodology used in the Carrington article2 was adopted for this study. The clinical foundation...

Source: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3721364

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Sep 22, 2013
09/13

by
Fang-Wei Fu; San Ling; Chaoping Xing

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In this paper, we study the following two hypercube coloring problems: Given $n$ and $d$, find the minimum number of colors, denoted as ${\chi}'_{d}(n)$ (resp. ${\chi}_{d}(n)$), needed to color the vertices of the $n$-cube such that any two vertices with Hamming distance at most $d$ (resp. exactly $d$) have different colors. These problems originally arose in the study of the scalability of optical networks. Using methods in coding theory, we show that ${\chi}'_{4}(2^{r+1}-1)=2^{2r+1}$,...

Source: http://arxiv.org/abs/1001.2209v1

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Sep 17, 2013
09/13

by
Stepan Grinek; Zhou Li; Jie Chen; Qinwei Shi; Frank Marsiglio

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We show that the changes in the electronic density of states (DOS) in graphene induced by impurity scattering with short-range potentials are completely different from those caused by the long-range Coulomb potential. The spectral weight of the state that eventually disappears into the valence band (as the strength of scattering increases) does not transform into a resonance state. Therefore no unusual screening effects related to a redistribution of the density of states in the valence band...

Source: http://arxiv.org/abs/0912.1532v3

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Sep 22, 2013
09/13

by
K. P. Esler; R. E. Cohen; B. Militzer; Jeongnim Kim; R. J. Needs; M. D. Towler

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We develop an all-electron quantum Monte Carlo (QMC) method for solids that does not rely on pseudopotentials, and use it to construct a primary ultra-high pressure calibration based the equation of state of cubic boron nitride(c-BN). We compute the static contribution to the free energy with QMC, and obtain the phonon contribution from density functional theory, yielding a high-accuracy calibration up to 900 GPa usable directly in experiment. Furthermore, we compute the anharmonic Raman...

Source: http://arxiv.org/abs/1001.2079v1

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Sep 19, 2013
09/13

by
Tim Bartley; Bettina Heim; Dominique Elser; Denis Sych; Metin Sabuncu; Christoffer Wittmann; Norbert Lindlein; Christoph Marquardt; Gerd Leuchs

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In our continuous variable quantum key distribution (QKD) scheme, the homodyne detection set-up requires balancing the intensity of an incident beam between two photodiodes. Realistic lens systems are insufficient to provide a spatially stable focus in the presence of large spatial beam-jitter caused by atmospheric transmission. We therefore present an improved geometry for optical tapers which offer up to four times the angular tolerance of a lens. The effective area of a photodiode can thus...

Source: http://arxiv.org/abs/0910.3063v2

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Sep 22, 2013
09/13

by
Lara B. Anderson; James Gray; Burt Ovrut

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A holomorphic vector bundle on a Calabi-Yau threefold, X, with h^{1,1}(X)>1 can have regions of its Kahler cone where it is slope-stable, that is, where the four-dimensional theory is N=1 supersymmetric, bounded by "walls of stability". On these walls the bundle becomes poly-stable, decomposing into a direct sum, and the low energy gauge group is enhanced by at least one anomalous U(1) gauge factor. In this paper, we show that these additional symmetries can strongly constrain the...

Source: http://arxiv.org/abs/1001.2317v1

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Sep 22, 2013
09/13

by
Benjamin R. Barsdell; David G. Barnes; Christopher J. Fluke

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Astronomers have come to rely on the increasing performance of computers to reduce, analyze, simulate and visualize their data. In this environment, faster computation can mean more science outcomes or the opening up of new parameter spaces for investigation. If we are to avoid major issues when implementing codes on advanced architectures, it is important that we have a solid understanding of our algorithms. A recent addition to the high-performance computing scene that highlights this point...

Source: http://arxiv.org/abs/1001.2048v1

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Sep 22, 2013
09/13

by
Fredrik Rusek; Angel Lozano; Nihar Jindal

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We present a method to compute, quickly and efficiently, the mutual information achieved by an IID (independent identically distributed) complex Gaussian input on a block Rayleigh-faded channel without side information at the receiver. The method accommodates both scalar and MIMO (multiple-input multiple-output) settings. Operationally, the mutual information thus computed represents the highest spectral efficiency that can be attained using standard Gaussian codebooks. Examples are provided...

Source: http://arxiv.org/abs/1001.2283v1

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Sep 22, 2013
09/13

by
Slawomir Klimek; Matthew McBride

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We study the index problem for the d-bar operators subject to Atiyah- Patodi-Singer boundary conditions on noncommutative disk and annulus.

Source: http://arxiv.org/abs/1001.2216v1

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Sep 22, 2013
09/13

by
Silke Henkes; Carolina Brito; Olivier Dauchot; Wim Van Saarloos

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Contacts at the Coulomb threshold are unstable to tangential perturbations and thus contribute to failure at the microscopic level. How is such a local property related to global failure, beyond the effective picture given by a Mohr-Coulomb type failure criterion? Here, we use a simulated bed of frictional disks slowly tilted under the action of gravity to investigate the link between the avalanche process and a global generalized isostaticity criterion. The avalanche starts when the packing as...

Source: http://arxiv.org/abs/1001.2202v1

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Sep 22, 2013
09/13

by
L. K. Dash; H. Ness; R. W. Godby

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We consider the interaction between electrons and molecular vibrations in the context of electronic transport in nanoscale devices. We present a method based on non-equilibrium Green's functions to calculate both equilibrium and non-equilibrium electronic properties of a single-molecule junction in the presence of electron-vibron interactions. We apply our method to a model system consisting of a single electronic level coupled to a single vibration mode in the molecule, which is in contact...

Source: http://arxiv.org/abs/1001.2115v1

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Sep 22, 2013
09/13

by
J. J. He; H. W. Wang; J. Hu; L. Li; L. Y. Zhang; M. L. Liu; S. W. Xu; X. Q. Yu

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The reaction rates of the key stellar reaction of $^{14}$O($\alpha$,p)$^{17}$F have been reexamined. The previous conclusion, the 6.15-MeV state ($J^{\pi}$=1$^-$) dominating this reaction rate, has been overthrown by a careful reanalysis of the previous experimental data [J. G\'{o}mez del Campo {\it et al.}, Phys. Rev. Lett. {\bf 86}, 43 (2001)]. According to the present $R$-matrix analysis, the previous 1$^-$ assignment for the 6.15-MeV state is definitely wrong. Most probably, the 6.286-MeV...

Source: http://arxiv.org/abs/1001.2053v1

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Sep 22, 2013
09/13

by
Christine Jacob

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Let $\{Z_n\}$ be a real nonstationary stochastic process such that $E(Z_n|{\mathcaligr F}_{n-1})\stackrel{\mathrm{a.s.}}{

Source: http://arxiv.org/abs/1001.2102v1

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Sep 23, 2013
09/13

by
Akihiro Nishiyama

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We study non-equilibrium quantum dynamics of the single-component scalar field theory in 1+1 space-time dimensions on the basis of the Kadanoff-Baym equation including the next-to-leading-order (NLO) skeleton diagrams. As an extension of the non-relativistic case, we derive relativistic kinetic entropy at the first order in the gradient expansion of the Kadanoff-Baym equations. The derived entropy satisfies the H theorem. Next we perform numerical simulations in spatially homogeneous...

Source: http://arxiv.org/abs/0810.5003v2

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Sep 22, 2013
09/13

by
S. Danilovic; M. Schuessler; S. K. Solanki

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We obtain information about the magnetic flux present in the quiet Sun by comparing radiative MHD simulations with Hinode/SP observations, with particular emphasis on the role of surface dynamo action. Simulation runs with different magnetic Reynolds numbers (Rm) are used together with observations at different heliocentric angles with different levels of noise. The results show that simulations with an imposed mixed-polarity field and Rm below the threshold for dynamo action reproduce the...

Source: http://arxiv.org/abs/1001.2183v1

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Sep 22, 2013
09/13

by
Giuseppe Pagliara; Matthias Hempel; Jurgen Schaffner-Bielich

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We consider the possible formation of the quark hadron mixed phase in protoneutron stars. We discuss two cases: the first one, corresponding to a vanishingly small value of the surface tension of quark matter, is the well known mixed phase in which the global electric charge neutrality condition is imposed. In turn, this produces a non-constant pressure mixed phase. In the second case, corresponding to very large values of the surface tension, the charge neutrality condition holds only locally....

Source: http://arxiv.org/abs/1001.2191v1

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Sep 22, 2013
09/13

by
T. Duric; D. K. K. Lee

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We study the Bose-condensed ground states of bosons in a two-dimensional optical lattice in the presence of frustration due to an effective vector potential, for example, due to lattice rotation. We use a mapping to a large-S frustrated magnet to study quantum fluctuations in the condensed state. Quantum effects are introduced by considering a 1/S expansion around the classical ground state. The large-S regime should be relevant to systems with many particles per site. As the system approaches...

Source: http://arxiv.org/abs/0906.1600v2

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Sep 22, 2013
09/13

by
Lukáš Vokřínek

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We gather conditions on a class H of continuous maps of topological spaces that allow a reasonable theory of fibrations up to an equivalence (a map from this class) which we call H-fibrations. The weak homotopy equivalences recover quasifibrations and homology equivalences yield homology fibrations. We study local H-fibrations that behave nicely with respect to homotopy colimits together with universal H-fibrations that behave nicely with respect to pullbacks. We then proceed to classify...

Source: http://arxiv.org/abs/1001.2056v1

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Sep 22, 2013
09/13

by
A. Asensio Ramos; J. Trujillo Bueno

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We explore the photospheric and chromospheric magnetic field in an emerging flux region. An image of the equivalent width of the He I 10830 A red blended component shows the presence of filamentary structures that might be interpreted as magnetic loops. We point out that the magnetic field strength in the chromosphere resembles a smoothed version of that found in the photosphere and that it is not correlated at all with the above-mentioned equivalent width map. Lacking other diagnostics, this...

Source: http://arxiv.org/abs/1001.2108v1

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Sep 22, 2013
09/13

by
Yun Soo Myung

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We find the entropy of Kehagias-Sfetsos black hole in the deformed Ho\v{r}ava-Lifshitz gravity by using the first law of thermodynamics. When applying generalized uncertainty principle (GUP) to Schwarzschild black hole, the entropy $S=A/4+(\pi/\omega)\ln(A/4)$ may be interpreted as the GUP-inspired black hole entropy. Hence, it implies that the duality in the entropy between the Kehagias-Sfetsos black hole and GUP-inspired Schwarzschild black hole is present.

Source: http://arxiv.org/abs/0908.4132v3

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Sep 22, 2013
09/13

by
Zheng Xie; Yujie Ma

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The Westervelt equation is a model for the propagation of finite amplitude ultrasound. The method of discrete exterior calculus can be used to solve this equation numerically. A significant advantage of this method is that it can be used to find numerical solutions in the discrete space manifold and the time, and therefore is a generation of finite difference time domain method. This algorithm has been implemented in C++.

Source: http://arxiv.org/abs/1001.2082v1

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Sep 22, 2013
09/13

by
H. B. Nersisyan; C. Toepffer; G. Zwicknagel

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The spectral line shapes for hydrogen-like heavy ion emitters embedded in strongly correlated two-component electron-ion plasmas are investigated with numerical simulations. For that purpose the microfield fluctuations are calculated by molecular dynamics simulations where short range quantum effects are taken into account by using a regularized Coulomb potential for the electron-ion interaction. The microfield fluctuations are used as input in a numerical solution of the time-dependent...

Source: http://arxiv.org/abs/1001.2103v1

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Sep 22, 2013
09/13

by
D. Kunik; L. I. Pietrasanta; O. E. Martínez

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A nanopatterning scheme is presented by which the structure height can be controlled in the tens of nanometers range and the lateral resolution is a factor at least three times better than the point spread function of the writing beam. The method relies on the initiation of the polymerization mediated by a very inefficient energy transfer from a fluorescent dye molecule after single photon absorption. The mechanism has the following distinctive steps: the dye adsorbs on the substrate surface...

Source: http://arxiv.org/abs/1001.2217v1

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Sep 17, 2013
09/13

by
Xian-Wei Kang; Hai-Bo Li

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In this paper, we intend to study the problem of CP violation in $D$ meson by $D\to VV$ decay mode in which the T violating triple-product correlation is examined. That would undoubtedly be another excellent probe of New Physics beyond Standard Model. For the neutral $D$, we focus on direct CP violation without considering $D^0-\bar D^0$ oscillation. Experimentally, by a full angular analysis one may obtain such CP violating signals, and particularly it is worth mentioning that the upcoming...

Source: http://arxiv.org/abs/0912.3068v2

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Sep 22, 2013
09/13

by
Elisabete da Cunha; Celine Eminian; Stephane Charlot; Jeremy Blaizot

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(Abridged) We assemble a sample of 3258 low-redshift galaxies from the SDSS DR6 with complementary photometric observations by GALEX, 2MASS and IRAS at far-ultraviolet and infrared wavelengths. We use a recent, simple but physically motivated model to interpret the observed spectral energy distributions of the galaxies in this sample in terms of statistical constraints on physical parameters describing the star formation history and dust content. The focus on a subsample of 1658 galaxies with...

Source: http://arxiv.org/abs/1001.2309v1

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Sep 23, 2013
09/13

by
Xin Qi; Hongyu Zhao

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Ordinary differential equations (ODEs) are commonly used to model dynamic behavior of a system. Because many parameters are unknown and have to be estimated from the observed data, there is growing interest in statistics to develop efficient estimation procedures for these parameters. Among the proposed methods in the literature, the generalized profiling estimation method developed by Ramsay and colleagues is particularly promising for its computational efficiency and good performance. In this...

Source: http://arxiv.org/abs/0903.3400v3

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Sep 22, 2013
09/13

by
Agnes Gadbled

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We describe families of monotone symplectic manifolds constructed via the symplectic cutting procedure of Lerman from the cotangent bundle of manifolds endowed with a free circle action. We also give obstructions to the monotone Lagrangian embedding of some compact manifolds in these symplectic manifolds.

Source: http://arxiv.org/abs/1001.2325v1

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Sep 22, 2013
09/13

by
Peter Olofsson

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We investigate the $x\log x$ condition for a general (Crump--Mode--Jagers) multi-type branching process with a general type space by constructing a size-biased population measure that relates to the ordinary population measure via an intrinsic martingale $W_t$. Sufficiency of the $x\log x$ condition for a non-degenerate limit of $W_t$ is proved and conditions for necessity are investigated.

Source: http://arxiv.org/abs/1001.2138v1

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Sep 22, 2013
09/13

by
C. E. Wolfe; K. Maltman

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We study the implications of several recent high-precision measurements of the pion form factor in the region of the rho-omega interference "shoulder" for (i) the extraction of the rho-omega mixing matrix element, Pi_{\rho\omega}(m_rho^2), and (ii) the evaluation of the isospin-breaking (IB) correction needed to incorporate hadronic tau decay data into the determination of the Standard Model expectation for the leading order hadronic contribution, [a_mu]_{had}^{LO}, to the anomalous...

Source: http://arxiv.org/abs/0908.2391v2

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Sep 22, 2013
09/13

by
Hao Li; Vladimir Nikiforov; Richard Schelp

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We introduce and study a new type of Ramsey-Turan problems, a typical example of which is the following one: let c>0 and G be a graph of sufficiently large order n with minimum degree >3n/4. If the edges of G are colored in blue or red, then for every 3

Source: http://arxiv.org/abs/1001.2078v1

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Sep 22, 2013
09/13

by
Otakar Svitek

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There are several fundamental differences between four-dimensional and higher-dimensional gravitational waves, namely in the so called braneworld set-up. One of them is their asymptotic behavior within the Cauchy problem. This study is connected with the so called Hadamard problem, which aims at the question of Huygens principle validity. We investigate the effect of braneworld scenarios on the character of propagation of gravitational waves on FRW background.

Source: http://arxiv.org/abs/1001.0198v2

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Sep 19, 2013
09/13

by
Michael Knap; Enrico Arrigoni; Wolfgang von der Linden

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Spectral properties of the two-dimensional Bose-Hubbard model, which emulates ultracold gases of atoms confined in optical lattices, are investigated by means of the variational cluster approach. The phase boundary of the quantum phase transition from Mott phase to superfluid phase is calculated and compared to recent work. Moreover the single-particle spectral functions in both the first and the second Mott lobe are presented and the corresponding densities of states and momentum distributions...

Source: http://arxiv.org/abs/0909.3228v3

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Sep 22, 2013
09/13

by
K. K. Jose; P. Uma; V. Seetha Lekshmi; H. J. Haubold

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Geometric generalized Mittag-Leffler distributions having the Laplace transform $\frac{1}{1+\beta\log(1+t^\alpha)},0 0$ is introduced and its properties are discussed. Autoregressive processes with Mittag-Leffler and geometric generalized Mittag-Leffler marginal distributions are developed. Haubold and Mathai (2000) derived a closed form representation of the fractional kinetic equation and thermonuclear function in terms of Mittag-Leffler function. Saxena et al (2002, 2004a,b) extended the...

Source: http://arxiv.org/abs/1001.2295v1

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Sep 17, 2013
09/13

by
Artur O. Lopes; Jairo K. Mengue

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We address the analysis of the following problem: given a real H\"older potential $f$ defined on the Bernoulli space and $\mu_f$ its equilibrium state, it is known that this shift-invariant probability can be weakly approximated by probabilities in periodic orbits associated to certain zeta functions. Given a H\"older function $f>0$ and a value $s$ such that $0 0$. We do not assume here the maximizing probability for $f$ is unique.

Source: http://arxiv.org/abs/0912.4771v2

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Sep 22, 2013
09/13

by
Benjamin D. G. Chandran; Bo Li; Barrett N. Rogers; Eliot Quataert; Kai Germaschewski

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We consider ion heating by turbulent Alfven waves (AWs) and kinetic Alfven waves (KAWs) with perpendicular wavelengths comparable to the ion gyroradius and frequencies smaller than the ion cyclotron frequency. When the turbulence amplitude exceeds a certain threshold, an ion's orbit becomes chaotic. The ion then interacts stochastically with the time-varying electrostatic potential, and the ion's energy undergoes a random walk. Using phenomenological arguments, we derive an analytic expression...

Source: http://arxiv.org/abs/1001.2069v1

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Sep 22, 2013
09/13

by
Michal Matuszewski; Ivan L. Garanovich; Andrey A. Sukhorukov

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We predict that stable mobile spatio-temporal solitons can exist in arrays of periodically curved optical waveguides. We find two-dimensional light bullets in one-dimensional arrays with harmonic waveguide bending and three-dimensional bullets in square lattices with helical waveguide bending using variational formalism. Stability of the light bullet solutions is confirmed by the direct numerical simulations which show that the light bullets can freely move across the curved arrays. This...

Source: http://arxiv.org/abs/1001.2107v1

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Sep 23, 2013
09/13

by
John E. Everett; Quintin G. Schiller; Ellen G. Zweibel

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Cosmic rays and magnetic fields can substantially impact the launching of large-scale galactic winds. Many researchers have investigated the role of cosmic rays; our group previously showed that a cosmic-ray and thermally-driven wind could explain soft X-ray emission towards the center of the Galaxy. In this paper, we calculate the synchrotron emission from our original wind model and compare it to observations; the synchrotron data shows that earlier assumptions about the launching conditions...

Source: http://arxiv.org/abs/0904.1964v2

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Sep 22, 2013
09/13

by
R. K. Saxena; A. M. Mathai; H. J. Haubold

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In view of the role of reaction equations in physical problems, the authors derive the explicit solution of a fractional reaction equation of general character, that unifies and extends earlier results. Further, an alternative shorter method based on a result developed by the authors is given to derive the solution of a fractional diffusion equation. Fox functions and Mittag-Leffler functions are used for closed-form representations of the solutions of the respective differential equations.

Source: http://arxiv.org/abs/1001.2293v1

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Sep 22, 2013
09/13

by
Sean Dobbs

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Using CLEO data, we report on the confirmation of the eta_b(1S0) ground state of bottomonium in the radiative decay Upsilon(3S) -> gamma eta_b. We determine its mass to be M(eta_b) = 9391.8 +- 6.6 +- 2.1 MeV, which corresponds to the hyperfine splitting Delta M_hf(1S) = 68.5 +- 6.6 +- 2.0 MeV, and the branching fraction B(Upsilon(3S) -> gamma eta_b) = (7.1 +- 1.8 +- 1.1) x 10^-4. These results agree with those previously reported by BaBar.

Source: http://arxiv.org/abs/1001.2238v1

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Sep 22, 2013
09/13

by
Tobias Renk; Holger Jaekel; Friedrich Jondral; Deniz Gunduz; Andrea Goldsmith

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We derive the outage capacity of a bursty version of the amplify-and-forward (BAF) protocol for small signal-to-noise ratios when incremental relaying is used. We show that the ratio between the outage capacities of BAF and the cut-set bound is independent of the relay position and that BAF is outage optimal for certain conditions on the target rate R. This is in contrast to decode-and-forward with incremental relaying, where the relay location strongly determines the performance of the...

Source: http://arxiv.org/abs/1001.2112v1

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Sep 22, 2013
09/13

by
A. Deano; D. Huybrechs; A. B. J. Kuijlaars

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In this paper we study the asymptotic behavior of a family of polynomials which are orthogonal with respect to an exponential weight on certain contours of the complex plane. The zeros of these polynomials are the nodes for complex Gaussian quadrature of an oscillatory integral on the real axis with a high order stationary point, and their limit distribution is also analyzed. We show that the zeros accumulate along a contour in the complex plane that has the S-property in an external field. In...

Source: http://arxiv.org/abs/1001.2219v1

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Sep 22, 2013
09/13

by
Bartolomeu F. Uchoa-Filho; Roberto W. Nobrega

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In this paper, we consider noncoherent random linear coding networks (RLCNs) as a discrete memoryless channel (DMC) whose input and output alphabets consist of subspaces. This contrasts with previous channel models in the literature which assume matrices as the channel input and output. No particular assumptions are made on the network topology or the transfer matrix, except that the latter may be rank-deficient according to some rank deficiency probability distribution. We introduce a random...

Source: http://arxiv.org/abs/1001.1021v2

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Sep 22, 2013
09/13

by
Toshiyuki Tanaka; Ryuhei Mori

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A rate-dependent upper bound of the best achievable block error probability of polar codes with successive-cancellation decoding is derived.

Source: http://arxiv.org/abs/1001.2067v1

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Sep 19, 2013
09/13

by
Fabrice Gerbier; Jean Dalibard

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We present a scheme that produces a strong U(1)-like gauge field on cold atoms confined in a two-dimensional square optical lattice. Our proposal relies on two essential features, a long-lived metastable excited state that exists for alkaline-earth or Ytterbium atoms, and an optical superlattice. As in the proposal by Jaksch and Zoller [New Journal of Physics 5, 56 (2003)], laser-assisted tunneling between adjacent sites creates an effective magnetic field. In the tight-binding approximation,...

Source: http://arxiv.org/abs/0910.4606v3

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Sep 17, 2013
09/13

by
L. Miller; T. J. Turner; J. N. Reeves; A. Lobban; S. B. Kraemer; D. M. Crenshaw

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Long-exposure Suzaku X-ray observations of the active galaxy NGC 4051 from 2005 and 2008 are analysed, in an attempt to reach a self-consistent understanding of the spectral variability on long timescales and at high time resolution. Principal components analysis and a maximum likelihood method of power spectrum analysis are used. In common with other type I AGN, the spectral variability is dominated by a varying-normalisation power-law component together with a quasi-steady, hard-spectrum...

Source: http://arxiv.org/abs/0912.0456v2

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Sep 22, 2013
09/13

by
V. O. Soloviev; M. V. Tchichikina

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We obtain the Poincare group generators by proper choice of arbitrary functions present in the Relativistic Theory of Gravitation (RTG) Hamiltonian. Their Dirac brackets give the Poincare algebra in accordance with the fact that RTG has 10 integrals of motion.

Source: http://arxiv.org/abs/1001.2099v1

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Sep 19, 2013
09/13

by
Johannes Bergstrom; Tommy Ohlsson

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We investigate the effect of unparticle self-interactions at the Large Hadron Collider (LHC). Especially, we discuss the three-point correlation function, which is determined by conformal symmetry up to a constant, and study its relation to processes with four-particle final states. These processes could be used as a favorable way to look for unparticle physics, and for weak enough couplings to the Standard Model, even the only way. We find updated upper bounds on the cross sections for...

Source: http://arxiv.org/abs/0909.2213v2

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Sep 22, 2013
09/13

by
Guo-Li Wang; Jin-Mei Zhang; Zhi-Hui Wang

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We analyzed the decays of $B^{+}\to {\bar {D}^0}+D^{+}_{sJ}(2S)$ and $B^{+}\to\bar D^{0}+D^{+}_{sJ}(1D)$ by naive factorization method and model dependent calculation based on the Bethe-Salpeter method, the branching ratios are $Br({\bar {D}^0}D^{+}_{sJ}(2S))=(0.72\pm0.12)%$ and $Br({\bar {D}^0}D^{+}_{sJ}(1D))=(0.027\pm0.007)%$. The branching ratio of decay $B^{+}\to {\bar {D}^0}D^{+}_{sJ}(2S)\to {\bar {D}^0}D^0 K^+$ consist with the data of Belle Collaboration, so we conclude that the new...

Source: http://arxiv.org/abs/1001.2035v1

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Sep 22, 2013
09/13

by
S. M. Hossein Tabatabaei Yazdi; Mohammad Reza Aref

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In this paper, we investigate optimal coding strategies for a class of linear deterministic relay networks. The network under study is a relay network, with one source, one destination, and two relay nodes. Additionally, there is a disturbing source of signals that causes interference with the information signals received by the relay nodes. Our model captures the effect of the interference of message signals and disturbing signals on a single relay network, or the interference of signals from...

Source: http://arxiv.org/abs/1001.2164v1

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Sep 22, 2013
09/13

by
K. Werner

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The hydrogen-deficiency in extremely hot post-AGB stars of spectral class PG1159 is probably caused by a (very) late helium-shell flash or a AGB final thermal pulse that consumes the hydrogen envelope, exposing the usually-hidden intershell region. Thus, the photospheric element abundances of these stars allow us to draw conclusions about details of nuclear burning and mixing processes in the precursor AGB stars. We compare predicted element abundances to those determined by quantitative...

Source: http://arxiv.org/abs/1001.2083v1